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<title>iOS短视频SDK开发指南.md</title><link href='http://fonts.googleapis.com/css?family=Open+Sans:400italic,700italic,700,400&subset=latin,latin-ext' rel='stylesheet' type='text/css'><style type='text/css'>html, body {overflow-x: initial !important;}.CodeMirror { height: auto; }
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<div  id='write'  class = 'is-mac'><p>版本：1.0.2</p><p>日期：2018-07-10</p><h1><a name='header-c9' class='md-header-anchor '></a>1.概述</h1><p>iOS短视频SDK是适用于iOS平台的短视频SDK。使用此SDK可以实现短视频相关功能。</p><h2><a name='header-c11' class='md-header-anchor '></a>1.1 功能特性</h2><table><thead><tr><th style='text-align:left;' >功能</th><th style='text-align:left;' >描述</th></tr></thead><tbody><tr><td style='text-align:left;' >拍摄</td><td style='text-align:left;' >支持短视频拍摄</td></tr><tr><td style='text-align:left;' >摄像头切换</td><td style='text-align:left;' >支持拍摄过程中切换摄像头</td></tr><tr><td style='text-align:left;' >断点拍摄</td><td style='text-align:left;' >支持拍摄过程中可暂停</td></tr><tr><td style='text-align:left;' >美颜滤镜</td><td style='text-align:left;' >支持拍摄加入美颜滤镜</td></tr><tr><td style='text-align:left;' >视频时长剪辑</td><td style='text-align:left;' >支持选取视频时长剪辑</td></tr><tr><td style='text-align:left;' >视频区域剪辑</td><td style='text-align:left;' >支持选取视频区域剪辑</td></tr></tbody></table><h2><a name='header-c35' class='md-header-anchor '></a>1.2阅读对象</h2><p>本文档为技术文档，需要阅读者：</p><ul><li>具备基本的iOS开发能力</li><li>准备接入CC视频的短视频SDK</li></ul><h1><a name='header-c45' class='md-header-anchor '></a>2.开发准备</h1><h2><a name='header-c46' class='md-header-anchor '></a>2.1开发环境</h2><ul><li>Xcode：苹果官方IDE</li><li>iOS8+</li></ul><h2><a name='header-c54' class='md-header-anchor '></a>2.2SDK使用说明</h2><p>首先，需要下载最新版本的SDK，下载地址为：<a href='https://github.com/CCVideo/VOD_iOS_ShortVideo_SDK'>VOD_iOS_ShortVideo_SDK</a>,然后导入SDK包到工程,在相应地方引入头文件<code>#import &quot;DWShortSDK&quot;</code></p><table><thead><tr><th style='text-align:left;' >名称</th><th style='text-align:left;' >描述</th></tr></thead><tbody><tr><td style='text-align:left;' >Demo</td><td style='text-align:left;' >使用SDK的示例源码</td></tr><tr><td style='text-align:left;' >doc</td><td style='text-align:left;' >存放的是iOS短视频SDK开发指南html文档</td></tr><tr><td style='text-align:left;' >include</td><td style='text-align:left;' >SDK开放的头文件及静态库</td></tr></tbody></table><h1><a name='header-c70' class='md-header-anchor '></a>3.快速集成</h1><p>注：快速集成主要提供的是拍摄功能</p><h2><a name='header-c72' class='md-header-anchor '></a>3.1拍摄快速集成</h2><h3><a name='header-c74' class='md-header-anchor '></a>3.1.1SDK添加到项目后，在info.plist文件设置麦克风 相机 相册 图片权限</h3><pre class='md-fences mock-cm' style='display:block;position:relative'>&lt;!-- 相册 --&gt;   
&lt;key&gt;NSPhotoLibraryUsageDescription&lt;/key&gt;   
&lt;string&gt;App需要您的同意,才能访问相册&lt;/string&gt;   
&lt;!-- 相机 --&gt;   
&lt;key&gt;NSCameraUsageDescription&lt;/key&gt;   
&lt;string&gt;App需要您的同意,才能访问相机&lt;/string&gt;   
&lt;!-- 麦克风 --&gt;   
&lt;key&gt;NSMicrophoneUsageDescription&lt;/key&gt;   
&lt;string&gt;App需要您的同意,才能访问麦克风&lt;/string&gt;
&lt;!-- 图片 --&gt; 
&lt;key&gt;NSPhotoLibraryAddUsageDescription&lt;/key&gt;
&lt;string&gt;App需要您的同意,才能保存图片到您的相册&lt;/string&gt;  </pre><h3><a name='header-c76' class='md-header-anchor '></a>3.1.2基于GPUImage 建议用cocoapods导入 也可手动导入 确保工程中只导入一次GPUImage</h3><h3><a name='header-c77' class='md-header-anchor '></a>3.1.3GPUImage引入后 修改以下部分：</h3><pre class='md-fences mock-cm' style='display:block;position:relative'>  1.GPUImageMovieWriter.h文件中添加isNeedBreakAudioWhiter属性
 
    @property (nonatomic, assign) BOOL isNeedBreakAudioWhiter;
 
  2.GPUImageMovieWriter.m文件中第377行代码修改如下：
    if (CMTIME_IS_INVALID(startTime))
     {
       if (_isNeedBreakAudioWhiter) {
 
 
      }else{
 
      runSynchronouslyOnContextQueue(_movieWriterContext, ^{
      if ((audioInputReadyCallback == NULL) &amp;&amp; (assetWriter.status != AVAssetWriterStatusWriting))
    {
       [assetWriter startWriting];
     }
       [assetWriter startSessionAtSourceTime:currentSampleTime];
       startTime = currentSampleTime;
 
     });
         
         }
 
    }
 
 3.GPUImageMovieWriter初始化时设置 isNeedBreakAudioWhiter =YES;
 具体详情参见demo</pre><h3><a name='header-c79' class='md-header-anchor '></a>3.1.3初始化相机及filterView</h3><pre class='md-fences mock-cm' style='display:block;position:relative'>//录制相关
    videoCamera = [[GPUImageVideoCamera alloc] initWithSessionPreset:AVCaptureSessionPreset1280x720
                                                      cameraPosition:AVCaptureDevicePositionBack];
    
    if ([videoCamera.inputCamera lockForConfiguration:nil]) {
        //自动对焦
        if ([videoCamera.inputCamera isFocusModeSupported:AVCaptureFocusModeContinuousAutoFocus]) {
            [videoCamera.inputCamera setFocusMode:AVCaptureFocusModeContinuousAutoFocus];
        }
        //自动曝光
        if ([videoCamera.inputCamera isExposureModeSupported:AVCaptureExposureModeContinuousAutoExposure]) {
            [videoCamera.inputCamera setExposureMode:AVCaptureExposureModeContinuousAutoExposure];
        }
        //自动白平衡
        if ([videoCamera.inputCamera isWhiteBalanceModeSupported:AVCaptureWhiteBalanceModeContinuousAutoWhiteBalance]) {
            [videoCamera.inputCamera setWhiteBalanceMode:AVCaptureWhiteBalanceModeContinuousAutoWhiteBalance];
        }
        
        [videoCamera.inputCamera unlockForConfiguration];
    }
    
    
    //输出方向为竖屏
    videoCamera.outputImageOrientation = UIInterfaceOrientationPortrait;
    //防止允许声音通过的情况下，避免录制第一帧黑屏闪屏
    [videoCamera addAudioInputsAndOutputs];
    videoCamera.horizontallyMirrorFrontFacingCamera = YES;
    videoCamera.horizontallyMirrorRearFacingCamera = NO;

    
    //显示view
    filterView =[[GPUImageView alloc]initWithFrame:[UIScreen mainScreen].bounds];
    [self.view addSubview:filterView];
    //组合
//    filter = [[GPUImageBilateralFilter alloc] init];
//    [videoCamera addTarget:filter];
//    [filter addTarget:filterView];
    
    
    [videoCamera addTarget:filterView];
     //相机开始运行
    [videoCamera startCameraCapture];
</pre><h3><a name='header-c81' class='md-header-anchor '></a>3.1.4初始化moviewriter</h3><pre class='md-fences mock-cm' style='display:block;position:relative'>    //写入
    movieWriter = [[GPUImageMovieWriter alloc] initWithMovieURL:videoURL size:CGSizeMake(720.0, 1280.0)];
    
    //设置为liveVideo
    movieWriter.isNeedBreakAudioWhiter =YES;
    movieWriter.encodingLiveVideo = YES;
    movieWriter.shouldPassthroughAudio =YES;
    
//  [filter addTarget:movieWriter];
    [videoCamera addTarget:movieWriter];

    //设置声音
    videoCamera.audioEncodingTarget = movieWriter;
</pre><h1><a name='header-c83' class='md-header-anchor '></a>4.功能使用</h1><h2><a name='header-c84' class='md-header-anchor '></a>4.1删除功能具体使用</h2><pre class='md-fences mock-cm' style='display:block;position:relative'>  //删除前要停止录制 
   if (isRecording) {
        
        [self stopWrite];
    }
     //读取文件 做个比对
    [self readShortVideoFiles];
    
    NSString *filePath =[self.pathArray lastObject];
    BOOL isSuccess = [DWShortTool dw_deleteFileWithFilePath:filePath];
    if (isSuccess) {
        
        
        self.videoArray =[[[NSUserDefaults standardUserDefaults] objectForKey:@&quot;videoArray&quot;] mutableCopy];
        [self.videoArray removeLastObject];
        [[NSUserDefaults standardUserDefaults] setObject:self.videoArray forKey:@&quot;videoArray&quot;];
        [[NSUserDefaults standardUserDefaults] synchronize];
        
        [self.pathArray removeLastObject];
        deleteBtn.hidden =self.pathArray.count&gt;0?NO:YES;
        
        UIView *view =[self.viewArray lastObject];
        [view removeFromSuperview];
        [self.viewArray removeLastObject];
        
        logdebug(@&quot;数组__%@__%@&quot;,self.pathArray,self.viewArray);
        //注意要减去相应的录制时间
        double recordTime =[[self.secondsArray lastObject] doubleValue];
        totalTime -=recordTime;
        [self.secondsArray removeLastObject];</pre><h2><a name='header-c86' class='md-header-anchor '></a>4.2切换功能具体使用</h2><pre class='md-fences mock-cm' style='display:block;position:relative'>   //前置摄像头不打开闪光灯
    if (videoCamera.inputCamera.position == AVCaptureDevicePositionFront) {
         return;
    }
    
    if (videoCamera.inputCamera.position == AVCaptureDevicePositionBack) {
       
      if (videoCamera.inputCamera.torchMode ==AVCaptureTorchModeOn) {
    
           [videoCamera.inputCamera lockForConfiguration:nil];
           [videoCamera.inputCamera setTorchMode:AVCaptureTorchModeOff];
           [videoCamera.inputCamera setFlashMode:AVCaptureFlashModeOff];
           [videoCamera.inputCamera unlockForConfiguration];
           //改变按钮状态
           lightBtn.selected =NO;
           
       }else{  
       
           [videoCamera.inputCamera lockForConfiguration:nil];
           [videoCamera.inputCamera setTorchMode:AVCaptureTorchModeOn];
           [videoCamera.inputCamera setFlashMode:AVCaptureFlashModeOn];
           [videoCamera.inputCamera unlockForConfiguration];
           //改变按钮状态
           lightBtn.selected =YES;
       
       }
        
    }
</pre><h2><a name='header-c88' class='md-header-anchor '></a>4.3美颜滤镜功能具体使用</h2><pre class='md-fences mock-cm' style='display:block;position:relative'> beautyBtn.selected =!beautyBtn.selected;
    if (beautyBtn.selected) {
        
        // 移除之前所有的处理链
        [videoCamera removeAllTargets];
        
        // 创建美颜滤镜
        filter = [[GPUImageBilateralFilter alloc] init];
        
        // 设置GPUImage处理链，从数据-&gt;滤镜-&gt;界面展示
        [videoCamera addTarget:filter];
        [filter addTarget:filterView];
        
      }else{
        
        // 移除之前所有的处理链
        [videoCamera removeAllTargets];
        [videoCamera addTarget:filterView];
    
 }
</pre><h2><a name='header-c90' class='md-header-anchor '></a>4.4暂停功能具体使用</h2><pre class='md-fences mock-cm' style='display:block;position:relative'> //因为GCDtimer较为精准 务必先调用移除定时器的方法 再调用停止录制的方法
    [self removeTimer];
    dispatch_async(dispatch_get_main_queue(), ^{
        //注意顺序
        [movieWriter finishRecording];
        [filter removeTarget:movieWriter];
        videoCamera.audioEncodingTarget = nil;
        
    });
    
    beautyBtn.hidden =NO;
    [self.secondsArray addObject:[NSString stringWithFormat:@&quot;%f&quot;,seconds]];
  //  [self saveModelToVideoArray];
    
    recordBtn.selected =NO;
    isRecording =NO;
    [self savePhotosAlbum:videoURL];
    logdebug(@&quot;录制时间为%f 当前时间为%f&quot;,seconds,totalTime);</pre><h2><a name='header-c92' class='md-header-anchor '></a>4.5断点拍摄功能具体使用</h2><p>断点拍摄后的几个小视频可以合成为一个视频, DWShortTool提供了如下接口用于合成视频:</p><pre class='md-fences mock-cm' style='display:block;position:relative'>/* 合成视频|转换视频格式
 @param videosPathArray:合成视频的路径数组
 @param outpath:输出路径
 @param outputFileType:视频格式 如：AVFileTypeQuickTimeMovie  AVFileTypeMPEG4等
 @param presetName:分辨率 如：AVAssetExportPresetMediumQuality AVAssetExportPreset640x480等
 @param  completeBlock  mergeFileURL:合成后新的视频URL
 */
+ (void)dw_mergeAndExportVideos:(NSArray *)videosPathArray withOutPath:(NSString *)outpath outputFileType:(NSString *)outputFileType  presetName:(NSString *)presetName  didComplete:(void(^)(NSError *error,NSURL *mergeFileURL) )completeBlock;

使用详情参见demo。</pre><h2><a name='header-c96' class='md-header-anchor '></a>4.6工具类DWShortTool开放的其它接口</h2><h3><a name='header-c97' class='md-header-anchor '></a>4.6.1视频压缩</h3><pre class='md-fences mock-cm' style='display:block;position:relative'>/**
 压缩视频

 @param videoPath 视频路径
 @param outPath 输出路径
 @param outputFileType 视频格式
 @param presetName 分辨率
 @param completeBlock 回调的block  compressionFileURL:压缩后的视频URL
 */
+ (void)dw_compressionAndExportVideo:(NSString *)videoPath withOutPath:(NSString *)outPath outputFileType:(NSString *)outputFileType  presetName:(NSString *)presetName  didComplete:(void(^)(NSError *error,NSURL *compressionFileURL) )completeBlock</pre><h3><a name='header-c99' class='md-header-anchor '></a>4.6.2选取视频时长剪辑</h3><pre class='md-fences mock-cm' style='display:block;position:relative'>/**
 视频时长剪辑 视频区域不变

 @param videoPath 视频路径
 @param outPath 视频输出路径
 @param outputFileType 视频格式
 @param presetName 分辨率
 @param timeRange 截取视频的时间范围
 @param completeBlock 回调的block  compressionFileURL:剪辑后的视频URL
 */
+ (void)dw_videoTimeCropAndExportVideo:(NSString *)videoPath withOutPath:(NSString *)outPath outputFileType:(NSString *)outputFileType  presetName:(NSString *)presetName range:(CMTimeRange )timeRange didComplete:(void(^)(NSError *error,NSURL *compressionFileURL) )completeBlock;
</pre><h3><a name='header-c101' class='md-header-anchor '></a>4.6.3视频区域裁剪</h3><pre class='md-fences mock-cm' style='display:block;position:relative'>/**
 视频区域剪裁 视频时长不变

 @param videoPath 视频路径
 @param outPath 视频输出路径
 @param outputFileType 视频格式
 @param presetName 分辨率
 @param videoSize 剪裁区域
 @param videoPoint 剪裁起点
 @param shouldScale 是否拉伸 YES拉伸 NO不拉伸 剪裁黑背景
 @param completeBlock 剪裁完成后的回调
 */
+ (void)dw_videoSizeCropAndExportVideo:(NSString *)videoPath withOutPath:(NSString *)outPath outputFileType:(NSString *)outputFileType  presetName:(NSString *)presetName size:(CGSize )videoSize point:(CGPoint )videoPoint shouldScale:(BOOL )shouldScale didComplete:(void(^)(NSError *error,NSURL *compressionFileURL) )completeBlock;
</pre><h3><a name='header-c103' class='md-header-anchor '></a>4.6.4视频区域兼时长剪裁</h3><pre class='md-fences mock-cm' style='display:block;position:relative'>/**
 视频区域兼时长剪裁
 
 @param videoPath 视频路径
 @param outPath 视频输出路径
 @param outputFileType 视频格式
 @param presetName 分辨率
 @param videoSize 剪裁区域
 @param videoPoint 剪裁起点
 @param shouldScale 是否拉伸 YES拉伸 NO不拉伸 剪裁黑背景
 @param timeRange 截取视频的时间范围
 @param completeBlock 剪裁完成后的回调
 */
+ (void)dw_videoSizeAndTimeCropAndExportVideo:(NSString *)videoPath withOutPath:(NSString *)outPath outputFileType:(NSString *)outputFileType  presetName:(NSString *)presetName size:(CGSize )videoSize point:(CGPoint )videoPoint shouldScale:(BOOL )shouldScale range:(CMTimeRange)timeRange didComplete:(void(^)(NSError *error,NSURL *compressionFileURL) )completeBlock;
</pre><h2><a name='header-c106' class='md-header-anchor '></a>4.7Demo具体使用</h2><p>Demo是示例源码，可直接用Xcode运行。Demo的设计旨在展示SDK各项功能的使用方法，如果希望应用获得更好的使用体验，要根据需求自行更改。
如果在使用SDK过程中遇到其他问题请联系CC客服进行反馈。</p><p></p><h1><a name='header-c112' class='md-header-anchor '></a>5.API查询</h1><p><a href='https://github.com/CCVideo/VOD_iOS_ShortVideo_SDK/blob/master/doc/api'>https://github.com/CCVideo/VOD_iOS_ShortVideo_SDK/tree/master/doc/api</a></p><h1><a name='header-c115' class='md-header-anchor '></a>6.Q&amp;A</h1><p></p></div>
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